<template>
  <ul class="app-header-nav">
    <li class="home"><RouterLink to="/">首页</RouterLink></li>
    <li v-for="item in list" :key="item.id" @mouseenter="show(item)" @mouseleave="hide(item)">
    <RouterLink @click="hide(item)" :to="`/category/${item.id}`">{{item.name}}</RouterLink>
       <div class="layer" :class="{open:item.open}">
        <ul>
          <li v-for="sub in item.children" :key="sub.id">
            <RouterLink @click="hide(item)" :to="`/category/sub/${sub.id}`">
              <img :src="sub.picture" alt="">
              <p>{{sub.name}}</p>
            </RouterLink>
          </li>
        </ul>
      </div>
    </li>
  </ul>
</template>

<script>
import {computed} from 'vue'
import {useStore} from 'vuex'
export default {
  name: 'AppHeaderNav',
  setup(){
    const store=useStore()
    //拿到vuex中的分类列表
    const list=computed(()=>{
      return store.state.category.list
    })

    //跳转的时候不会关闭二级类目，通过数据来控制
    //1.vuex每个分类加上open数据
    //2.vuex提供显示和隐藏函数，修改open数据
    //3.组件中使用vuex中的函数，使用时间来绑定，提供一个类名显示隐藏的类名
    const show=(item)=>{
      store.commit('category/show',item.id)
    }
     const hide=(item)=>{
      store.commit('category/hide',item.id)
     }
    return { list,show,hide }
  }
}
</script>

<style scoped lang='less'>
.app-header-nav {
  width: 820px;
  display: flex;
  padding-left: 40px;
  position: relative;
  z-index: 998;
  > li {
    margin-right: 40px;
    width: 38px;
    text-align: center;
   > a {
      font-size: 16px;
      line-height: 32px;
      height: 32px;
      display: inline-block;
    }
    &:hover {
     > a {
        color: @xtxColor;
        border-bottom: 1px solid @xtxColor;
      }
      //显示二级类目
      //  > .layer {
      //   height: 132px;
      //   opacity: 1;
      // }
    }
  }
}
//二级类名弹层
.layer {
  &.open{
       height: 132px;
       opacity: 1;
  }
  width: 1240px;
  background-color: #fff;
  position: absolute;
  left: -200px;
  top: 56px;
  height: 0;
  overflow: hidden;
  opacity: 0;
  box-shadow: 0 0 5px #ccc;
  transition: all .2s .1s;
  ul {
    display: flex;
    flex-wrap: wrap;
    padding: 0 70px;
    align-items: center;
    height: 132px;
    li {
      width: 110px;
      text-align: center;
      img {
        width: 60px;
        height: 60px;
      }
      p {
        padding-top: 10px;
      }
      &:hover {
        p {
          color: @xtxColor;
        }
      }
    }
  }
}
</style>
